The RCBS Uniflow is a very good powder measure.

The BEST powder measure I have ever used is the charge bar on a Lee Load-All shotgun reloader. Before I could afford a Uniflow, I discovered the charge bar could dispense consistent loads of powder provided you tapped the front of the unit rather forcefully.

With the right bushing that Load-All would dispense 20.3 grains of IMR-4198 time after time after time (at the time that was a below Maximum load per Hornady #4) but today it would be above maximum.